ImageButton(): clarify purpose of size. (#6901, #5533, #4471, #2464, #1390).

Amend 4a2ae06ca

imgui.h

@@ -520,8 +520,9 @@ namespace ImGui
 
     // Widgets: Images
     // - Read about ImTextureID here: https://github.com/ocornut/imgui/wiki/Image-Loading-and-Displaying-Examples
+    // - Note that ImageButton() adds style.FramePadding*2.0f to provided size. This is in order to facilitate fitting an image in a button.
     IMGUI_API void          Image(ImTextureID user_texture_id, const ImVec2& size, const ImVec2& uv0 = ImVec2(0, 0), const ImVec2& uv1 = ImVec2(1, 1), const ImVec4& tint_col = ImVec4(1, 1, 1, 1), const ImVec4& border_col = ImVec4(0, 0, 0, 0));
-    IMGUI_API bool          ImageButton(const char* str_id, ImTextureID user_texture_id, const ImVec2& size, const ImVec2& uv0 = ImVec2(0, 0), const ImVec2& uv1 = ImVec2(1, 1), const ImVec4& bg_col = ImVec4(0, 0, 0, 0), const ImVec4& tint_col = ImVec4(1, 1, 1, 1));
+    IMGUI_API bool          ImageButton(const char* str_id, ImTextureID user_texture_id, const ImVec2& image_size, const ImVec2& uv0 = ImVec2(0, 0), const ImVec2& uv1 = ImVec2(1, 1), const ImVec4& bg_col = ImVec4(0, 0, 0, 0), const ImVec4& tint_col = ImVec4(1, 1, 1, 1));
 
     // Widgets: Combo Box (Dropdown)
     // - The BeginCombo()/EndCombo() api allows you to manage your contents and selection state however you want it, by creating e.g. Selectable() items.

imgui_internal.h

@@ -3273,7 +3273,7 @@ namespace ImGui
     IMGUI_API void          TextEx(const char* text, const char* text_end = NULL, ImGuiTextFlags flags = 0);
     IMGUI_API bool          ButtonEx(const char* label, const ImVec2& size_arg = ImVec2(0, 0), ImGuiButtonFlags flags = 0);
     IMGUI_API bool          ArrowButtonEx(const char* str_id, ImGuiDir dir, ImVec2 size_arg, ImGuiButtonFlags flags = 0);
-    IMGUI_API bool          ImageButtonEx(ImGuiID id, ImTextureID texture_id, const ImVec2& size, const ImVec2& uv0, const ImVec2& uv1, const ImVec4& bg_col, const ImVec4& tint_col, ImGuiButtonFlags flags = 0);
+    IMGUI_API bool          ImageButtonEx(ImGuiID id, ImTextureID texture_id, const ImVec2& image_size, const ImVec2& uv0, const ImVec2& uv1, const ImVec4& bg_col, const ImVec4& tint_col, ImGuiButtonFlags flags = 0);
     IMGUI_API void          SeparatorEx(ImGuiSeparatorFlags flags, float thickness = 1.0f);
     IMGUI_API void          SeparatorTextEx(ImGuiID id, const char* label, const char* label_end, float extra_width);
     IMGUI_API bool          CheckboxFlags(const char* label, ImS64* flags, ImS64 flags_value);

imgui_widgets.cpp

@@ -1033,7 +1033,7 @@ void ImGui::Image(ImTextureID user_texture_id, const ImVec2& size, const ImVec2&
 
 // ImageButton() is flawed as 'id' is always derived from 'texture_id' (see #2464 #1390)
 // We provide this internal helper to write your own variant while we figure out how to redesign the public ImageButton() API.
-bool ImGui::ImageButtonEx(ImGuiID id, ImTextureID texture_id, const ImVec2& size, const ImVec2& uv0, const ImVec2& uv1, const ImVec4& bg_col, const ImVec4& tint_col, ImGuiButtonFlags flags)
+bool ImGui::ImageButtonEx(ImGuiID id, ImTextureID texture_id, const ImVec2& image_size, const ImVec2& uv0, const ImVec2& uv1, const ImVec4& bg_col, const ImVec4& tint_col, ImGuiButtonFlags flags)
 {
     ImGuiContext& g = *GImGui;
     ImGuiWindow* window = GetCurrentWindow();
@@ -1041,7 +1041,7 @@ bool ImGui::ImageButtonEx(ImGuiID id, ImTextureID texture_id, const ImVec2& size
         return false;
 
     const ImVec2 padding = g.Style.FramePadding;
-    const ImRect bb(window->DC.CursorPos, window->DC.CursorPos + size + padding * 2.0f);
+    const ImRect bb(window->DC.CursorPos, window->DC.CursorPos + image_size + padding * 2.0f);
     ItemSize(bb);
     if (!ItemAdd(bb, id))
         return false;
@@ -1060,14 +1060,15 @@ bool ImGui::ImageButtonEx(ImGuiID id, ImTextureID texture_id, const ImVec2& size
     return pressed;
 }
 
-bool ImGui::ImageButton(const char* str_id, ImTextureID user_texture_id, const ImVec2& size, const ImVec2& uv0, const ImVec2& uv1, const ImVec4& bg_col, const ImVec4& tint_col)
+// Note that ImageButton() adds style.FramePadding*2.0f to provided size. This is in order to facilitate fitting an image in a button.
+bool ImGui::ImageButton(const char* str_id, ImTextureID user_texture_id, const ImVec2& image_size, const ImVec2& uv0, const ImVec2& uv1, const ImVec4& bg_col, const ImVec4& tint_col)
 {
     ImGuiContext& g = *GImGui;
     ImGuiWindow* window = g.CurrentWindow;
     if (window->SkipItems)
         return false;
 
-    return ImageButtonEx(window->GetID(str_id), user_texture_id, size, uv0, uv1, bg_col, tint_col);
+    return ImageButtonEx(window->GetID(str_id), user_texture_id, image_size, uv0, uv1, bg_col, tint_col);
 }
 
 #ifndef IMGUI_DISABLE_OBSOLETE_FUNCTIONS